That is one of the reasons some governments have now stopped pushing the cashless society. In the Netherlands this realisation has set in, and the central bank now explicitly recommends people keep a sensible stash of cash for the inevitable (short term) crisis. Cash is a very useful tool when your digital infrastructure is being targetted.
Personally, while I will gladly pay with a contactless debit card, I refuse to shop at places which refuse cash. In the Netherlands, this is still rare though.
Besides, what about tourism? Even within Europe there is no guarantee my cards will just work in all places. Mostly? Yes. Always? Nope. Card fails? Just switch to cash. Going antiquing, or rifling through second hand book stalls at a book fair? Cash only is quite common there. It's not like I'll ever travel without cash.
Personally, while I will gladly pay with a contactless debit card, I refuse to shop at places which refuse cash. In the Netherlands, this is still rare though.
Besides, what about tourism? Even within Europe there is no guarantee my cards will just work in all places. Mostly? Yes. Always? Nope. Card fails? Just switch to cash. Going antiquing, or rifling through second hand book stalls at a book fair? Cash only is quite common there. It's not like I'll ever travel without cash.